I want you all to imagine feeling rested, alert and all of that on just a few hours of sleep a night. For most of us that the greatest sounding thing we've ever heard. It is just not happening. However, scientists say that for a lucky few there's never a need for an alarm clock, a cup of coffee. ABC's Mara schiavocampo has these short sleeper stories. Reporter: Sleep, it's the one thing almost nobody gets enough of. Unless you're one of these guys. Jen gets four hours of sleep every single day. She's not an insomniac. She's not sleep deprived and she's never tired. I feel like I'm living my life rather than sleeping it. Reporter: She is what's known as a short sleeper. Just like her dad. He can get by on as little as one hour of sleep a day. Not Superman. Not an x-man. Just feel lucky. Reporter: It's not luck, it's genetics. Researchers say thanks to a genetic mutation these real-life superhumans simply compress the brain's sleep cycles into half the time. They can't sleep more than a few hours even if they try, never use an alarm clock, rarely yawn and never nap. They're optimistic and go getters. Reporter: Lots of people claim to sleep very little including bill Clinton, Donald Trump and Martha Stewart but researchers say most of them are probably just sleep deprived and less than 1% of the population did made up of genuine short sleepers. I am definitely not one of them. I gave the whole short sleeping thing a try. I feel tired. I feel irritable and just not ready for the day. I wasn't just cranky, take a look at this reaction test. After one night of short sleep, I can't catch this pen at all. But schwanner living on four hours of sleep her entire life never misses. When we tested reaction time with a 15-inch ruler I kept getting worse. 11 inches. 12. 13. As for schwanner she did three types better than me getting more out of life. Four. Reporter: On a lot less sleep. Four. Reporter: For "Good morning America," Mara schiavocampo, ABC news, New York.

This transcript has been automatically generated and may not be 100% accurate.

{"id":22715333,"title":"Awake and Alert With Six Hours or Less?","duration":"3:00","description":"Researchers say less than 1 percent of the population is made up of \"short sleepers.\"","url":"/GMA/video/awake-alert-hours-22715333","section":"GMA","mediaType":"default"}